Eviscerate damage is too low

[Valendor]

I am a level 30 rogue now.
The tooltip of Eviscerate states the following:

1 Point: 41 - 61 damage
2 Points: 72 - 92 damage
3 Points: 103-123 damage
4 Points: 134-154 damage
5 Points: 165-185 damage

When i have 3 combopoints, i should get a minimum of 103 damage, acording to the tooltip.
However, it only gives me 88 damages, as if i had 2 combopoints
When i have 4 combopoints, i should get at least 134 damage of.
However, it only gives me 123 damage
It seems like the tooltip is wrong or the damage is too low by 1 comobopoint every time.

[Balake]

If you think the damage is too low by 1 combopoint every time, try it with 1 combo point and see the lowest and highest possible damage you can get. Mobs have armor, and it reduces the physical damage they take.

[Roxanneflowers]

Mobs have armor, and it reduces the physical damage they take.

This.

[Kalocsa]

Armor.
Instead of "HOLY STRIKE", Eviscerate final damages are scalled on the armor of your target.
Even if this is static damage; non-influenced by AP (the only possibility to increase the eviscerate damage is the 5/5 t2,5 gear, and the 3/3 assassination talent at the beginning of the three.

[Balake]

I think Blizzard made Eviscerate scale with attack power some time in late vanilla so it should scale here too.

[Kalocsa]

I think Blizzard made Eviscerate scale with attack power some time in late vanilla so it should scale here too.

Absolutely not. and, no.

[Gilgarosh]

I think Blizzard made Eviscerate scale with attack power some time in late vanilla so it should scale here too.

Absolutely not. and, no.

From patch 1.12's patch notes, "Eviscerate: Manual of Eviscerate (Rank 9) now drops off Blackhand Assassins in Black Rock Spire. In addition, Eviscerate now increases in potency with greater attack power."

EDIT: To clarify about the reduction of damage, Eviscerate deals physical damage, so it will be reduced by armor, which is likely what OP is experiencing.

[Xerron]

It is already increased by attack power, as the tooltip says
https://database.turtle-wow.org/?spell=31016